A PROSPECTIVE, DOUBLE-BLIND, RANDOMIZED STUDY OF HIGH-VERSUS LOW-DOSEOKT3 INDUCTION IMMUNOSUPPRESSION IN CADAVERIC RENAL-TRANSPLANTATION

We undertook a prospective, double-blind study of high-(5-mg) versus l ow-(2-mg) dose OKT3 for induction immunosuppression 12 days) in cadave ric (renal allograft transplantation. Maintenance immunosuppression wa s identical in both groups and consisted of azathioprine and prednison e initially, with cyclosporine beginning on the 5th postoperative day. Twenty-six patients were randomized. The groups were similar in terms of age, kidney ischemia time, peak PRA, and latest PRA. There were mo re diabetics and women in the high-dose group. Patient survival at 12 months was 100% in both groups. Graft survival at 12 months was 92% an d 100% in the high- and low-dose groups, respectively. Infections were mostly minor and equal in frequency in the two groups. All patients r eceiving high- or low-dose OKT3 had manifestations of the cytokine rel ease syndrome; these were delayed in onset in the low-dose group. Elev en patients (85%) in each group produced anti-OKT3 antibodies. Lymphoc yte depletion after 1 day was major (> 98%) and identical in both grou ps. CD3 antigens were removed more slowly in the low-dose group but ev entually at equal rates in both groups. Cost was significantly lower i n the low-dose group. We conclude that while both doses of OKT3 were e ffective and safe for induction immunosuppression, it may be prudent t o use a lower dose of OKT3 for induction immunosuppression because of its potential to reduce cytokine-mediated effects and to avoid the com plications of overimmunosuppression and because of the lower costs ass ociated with it.